| 1 | /* Handling of inferior events for the event loop for GDB, the GNU debugger. |
| 2 | Copyright (C) 1999-2014 Free Software Foundation, Inc. |
| 3 | Written by Elena Zannoni <ezannoni@cygnus.com> of Cygnus Solutions. |
| 4 | |
| 5 | This file is part of GDB. |
| 6 | |
| 7 | This program is free software; you can redistribute it and/or modify |
| 8 | it under the terms of the GNU General Public License as published by |
| 9 | the Free Software Foundation; either version 3 of the License, or |
| 10 | (at your option) any later version. |
| 11 | |
| 12 | This program is distributed in the hope that it will be useful, |
| 13 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 14 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 15 | GNU General Public License for more details. |
| 16 | |
| 17 | You should have received a copy of the GNU General Public License |
| 18 | along with this program. If not, see <http://www.gnu.org/licenses/>. */ |
| 19 | |
| 20 | #include "defs.h" |
| 21 | #include "inferior.h" /* For fetch_inferior_event. */ |
| 22 | #include "target.h" /* For enum inferior_event_type. */ |
| 23 | #include "event-loop.h" |
| 24 | #include "event-top.h" |
| 25 | #include "inf-loop.h" |
| 26 | #include "remote.h" |
| 27 | #include "exceptions.h" |
| 28 | #include "language.h" |
| 29 | #include "gdbthread.h" |
| 30 | #include "continuations.h" |
| 31 | #include "interps.h" |
| 32 | #include "top.h" |
| 33 | |
| 34 | static int fetch_inferior_event_wrapper (gdb_client_data client_data); |
| 35 | |
| 36 | /* General function to handle events in the inferior. So far it just |
| 37 | takes care of detecting errors reported by select() or poll(), |
| 38 | otherwise it assumes that all is OK, and goes on reading data from |
| 39 | the fd. This however may not always be what we want to do. */ |
| 40 | void |
| 41 | inferior_event_handler (enum inferior_event_type event_type, |
| 42 | gdb_client_data client_data) |
| 43 | { |
| 44 | struct cleanup *cleanup_if_error = make_bpstat_clear_actions_cleanup (); |
| 45 | |
| 46 | switch (event_type) |
| 47 | { |
| 48 | case INF_REG_EVENT: |
| 49 | /* Use catch errors for now, until the inner layers of |
| 50 | fetch_inferior_event (i.e. readchar) can return meaningful |
| 51 | error status. If an error occurs while getting an event from |
| 52 | the target, just cancel the current command. */ |
| 53 | if (!catch_errors (fetch_inferior_event_wrapper, |
| 54 | client_data, "", RETURN_MASK_ALL)) |
| 55 | { |
| 56 | bpstat_clear_actions (); |
| 57 | do_all_intermediate_continuations (1); |
| 58 | do_all_continuations (1); |
| 59 | async_enable_stdin (); |
| 60 | display_gdb_prompt (0); |
| 61 | } |
| 62 | break; |
| 63 | |
| 64 | case INF_EXEC_COMPLETE: |
| 65 | if (!non_stop) |
| 66 | { |
| 67 | /* Unregister the inferior from the event loop. This is done |
| 68 | so that when the inferior is not running we don't get |
| 69 | distracted by spurious inferior output. */ |
| 70 | if (target_has_execution) |
| 71 | target_async (NULL, 0); |
| 72 | } |
| 73 | |
| 74 | /* Do all continuations associated with the whole inferior (not |
| 75 | a particular thread). */ |
| 76 | if (!ptid_equal (inferior_ptid, null_ptid)) |
| 77 | do_all_inferior_continuations (0); |
| 78 | |
| 79 | /* If we were doing a multi-step (eg: step n, next n), but it |
| 80 | got interrupted by a breakpoint, still do the pending |
| 81 | continuations. The continuation itself is responsible for |
| 82 | distinguishing the cases. The continuations are allowed to |
| 83 | touch the inferior memory, e.g. to remove breakpoints, so run |
| 84 | them before running breakpoint commands, which may resume the |
| 85 | target. */ |
| 86 | if (non_stop |
| 87 | && target_has_execution |
| 88 | && !ptid_equal (inferior_ptid, null_ptid)) |
| 89 | do_all_intermediate_continuations_thread (inferior_thread (), 0); |
| 90 | else |
| 91 | do_all_intermediate_continuations (0); |
| 92 | |
| 93 | /* Always finish the previous command before running any |
| 94 | breakpoint commands. Any stop cancels the previous command. |
| 95 | E.g. a "finish" or "step-n" command interrupted by an |
| 96 | unrelated breakpoint is canceled. */ |
| 97 | if (non_stop |
| 98 | && target_has_execution |
| 99 | && !ptid_equal (inferior_ptid, null_ptid)) |
| 100 | do_all_continuations_thread (inferior_thread (), 0); |
| 101 | else |
| 102 | do_all_continuations (0); |
| 103 | |
| 104 | /* When running a command list (from a user command, say), these |
| 105 | are only run when the command list is all done. */ |
| 106 | if (interpreter_async) |
| 107 | { |
| 108 | volatile struct gdb_exception e; |
| 109 | |
| 110 | check_frame_language_change (); |
| 111 | |
| 112 | /* Don't propagate breakpoint commands errors. Either we're |
| 113 | stopping or some command resumes the inferior. The user will |
| 114 | be informed. */ |
| 115 | TRY_CATCH (e, RETURN_MASK_ALL) |
| 116 | { |
| 117 | bpstat_do_actions (); |
| 118 | } |
| 119 | exception_print (gdb_stderr, e); |
| 120 | } |
| 121 | break; |
| 122 | |
| 123 | case INF_EXEC_CONTINUE: |
| 124 | /* Is there anything left to do for the command issued to |
| 125 | complete? */ |
| 126 | |
| 127 | if (non_stop) |
| 128 | do_all_intermediate_continuations_thread (inferior_thread (), 0); |
| 129 | else |
| 130 | do_all_intermediate_continuations (0); |
| 131 | break; |
| 132 | |
| 133 | case INF_TIMER: |
| 134 | default: |
| 135 | printf_unfiltered (_("Event type not recognized.\n")); |
| 136 | break; |
| 137 | } |
| 138 | |
| 139 | discard_cleanups (cleanup_if_error); |
| 140 | } |
| 141 | |
| 142 | static int |
| 143 | fetch_inferior_event_wrapper (gdb_client_data client_data) |
| 144 | { |
| 145 | fetch_inferior_event (client_data); |
| 146 | return 1; |
| 147 | } |